1. Field
Apparatuses and methods consistent with exemplary embodiments relate to a spatial light modulator that modulates a phase of light by using a surface plasmon, a holographic three-dimensional (3D) image display including the spatial light modulator, and a method for modulating spatial light, whereby a phase of light is modulated by using a surface plasmon.
2. Description of the Related Art
As the technologies related to the 3D image display have considerably advanced, many three-dimensional (3D) movies have been recently released. To provide a three-dimensional effect, 3D image displays display 3D images using binocular parallax and respectively provide a left-eye image and a right-eye image having different view points to a viewer's left and right eyes. Such 3D image displays include glasses 3D image displays that require specific glasses and non-glasses 3D image displays that require no glasses.
However, when a 3D image displayed in a binocular parallax manner is viewed, a sense of eye fatigue is large, and 3D image displays that provide only a left-eye image and a right-eye image seen from two different view points cannot accurately reflect a change in the view points caused by the movement of the viewer, and thus have limitations in providing a sense of a natural three-dimensional effect.
To address this problem, holographic 3D image displays have been studied so as to display more natural three-dimensional images. Light may be regarded as having wave-like characteristics such as intensity and phase. Liquid crystal displays (LCDs) use an intensity spatial light modulator that controls the intensity of light. When holographic techniques are used, images are displayed by controlling the phase and intensity of light. Thus, holographic 3D image displays require a device capable of controlling the amplitude (intensity) or phase of light.
When holographic 3D image display methods are used, 3D images are obtained by writing and reproducing interference signals obtained by overlapping light from a subject with coherent reference light. Several holographic techniques, such as a pulse hologram method for capturing a moving picture image, a stereo hologram method that enables display of a wide space scene and a wide viewing angle, an embossed hologram method to mass-produce embossed holograms, a natural color hologram method that displays natural colors, digital holography using a digital photographing device, and electron holography for displaying an electronic hologram, have been developed. For example, in electron holography, an image captured from an original object is scanned according to each pixel and transmitted to an image processor, a hologram is created, data included in the hologram is sampled and transmitted to the image processor, the hologram is restored from the transmitted data, and the original object is displayed on a display device.
However, since the amount of data included in the hologram is too large to be sampled and transmitted to the image processor, a study for displaying a hologram created by using a computer in an electro-optic manner has been carried out. Also, several hologram systems for addressing the limitations of the current hologram devices have been studied. For example, a technique has been developed to display a hologram by using an eye-tracking method so as to reduce the amount of calculated data of the hologram and a study has been carried out to use a hologram optical device including a spatial light modulator and an improved hologram writing method in electron holography.